The crossword solution for the term 'war loser, usually' is TREY. This is a reference to the phrase 'treaty of peace, ' which is a document that is signed by two or more parties to officially end a war. A treaty of peace typically includes terms such as reparations, territorial adjustments, and other conditions that must be met in order for the war to be considered over. The losing side of the war is usually required to sign the treaty of peace, thus making them the 'war loser, usually.'